AB1490 OVERLAPPING INFLAMMATORY DISEASES IN HIDRADENITIS SUPPURATIVA PATIENTS AND THEIR FAMILIES
Authors: E. Er Gülbezer, S. Vural
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Hidradenitis suppurativa (HS) is an inflammatory disorder characterized by chronic deep-seated nodules, sinus tracts, and scars in the intertriginous areas. A significant decrease in quality of life accompanies chronic pain of active lesions. Association with inflammatory bowel disease (IBD) and spondyloarthropathies suggest an inflammatory signature overlap with rheumatological disorders. <h3>Objectives</h3> Based on the idea that the association of HS and rheumatological disease is more important and frequent than previously thought, we aimed to evaluate the symptoms and findings of rheumatological diseases in our HS patients. <h3>Methods</h3> Consecutive HS patients presented to the dermatology outpatient clinic between 2021-2022 are included in the study. Among the HS patients who applied to dermatology between 2021 and 2022, patients with arthralgia and low back pain were referred to the rheumatology department for evaluation. Family history was taken in detail for inflammatory conditions. Acute phase reactants were analysed. <h3>Results</h3> The group comprised 55 HS patients, including sixteen Hurley stage I (27.2%), 24 Hurley stage II (41.8%), and 14 (23.6%) Hurley stage III patients. The mean age of onset for HS was 28.8 (min:14, max:56). 51% (N=28) were women. Family history for HS was present in 14 (25.4%) patients. Twenty-four (43.6%) of 55 HS patients who applied to the dermatology outpatient clinic had an autoinflammatory/autoimmune disease diagnosis or inflammatory symptom/finding other than HS (Table 1). Sixteen (29%) patients described arthralgia and were referred to the rheumatology outpatient clinic. Among the HS patients, 32.7% had a significant autoimmune or autoinflammatory condition other than HS in 1<sup>st</sup> or 2<sup>nd</sup>-degree relatives. Positive family history for inflammatory processes other than HS was present in 10 (41.6%) patients with an additional inflammatory condition and 8 (25.8%) patients without a different inflammatory disease. Family history of inflammatory disorders include (Familial Mediterranean fever, acne conglabata, inflammatory bowel disease, psoriasis, Takayasu arteritis, amyloidosis, ankylosing spondylitis, uveitis, erythema nodosum, Behçet's disease and vitiligo. Serum amyloid A levels (SAA) were calculated in 16 patients, and 62.5% had elevated SAA levels. <h3>Conclusion</h3> Autoinflammatory rheumatological diseases or rheumatological symptoms were present in a significant proportion of HS patients. Prominent family history of inflammatory diseases suggests common genetic pathways in this spectrum of diseases. In addition, detailed history taking, including rheumatological symptoms in HS patients, is valuable and crucial in determining the extent of inflammation. <h3>References</h3> [1]Goldburg SR, Strober BE, Payette MJ, Part I. Hidradenitis Suppurativa: Epidemiology, clinical presentation, and pathogenesis, Journal of the American Academy of Dermatology (2019). doi: https://doi.org/10.1016/j.jaad.2019.08.090 [2]Kridin K, Shani M, Schonmann Y, et al. Psoriasis and Hidradenitis Suppurativa: A Large-scale 532 Population-based Study. J Am Acad Dermatol. November 2018. doi: 10.1016/j.jaad.2018.11.036 [3]Principi M, Cassano N, Contaldo A, et al. Hydradenitis suppurativa and inflammatory bowel 537 disease: An unusual, but existing association. World J Gastroenterol. 2016;22(20):4802-4811. 538 doi:10.3748/wjg. v22.i20.4802 [4]Ramos-Rodriguez AJ, Timerman D, Khan A, Bonomo L, Hunjan MK, Lemor A. The in-hospital 540 burden of hidradenitis suppurativa in patients with inflammatory bowel disease: a decade 541 nationwide analysis from 2004 to 2014. Int J Dermatol. 2018;57(5):547-552. 542 doi:10.1111/ijd.13932 [5]Richette P, Molto A, Viguier M, et al. Hidradenitis suppurativa associated with spondyloarthritis -- 544 results from a multicenter national prospective study. J Rheumatol. 2014;41(3):490-494. 545 doi:10.3899/jrheum.130977 <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.